• Title/Summary/Keyword: Image Coding

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Upregulation of thiamine (vitamin B1) biosynthesis gene upon stress application in Anabaena sp. and Nannochloropsis oculata

  • Fern, Lee Li;Abidin, Aisamuddin Ardi Zainal;Yusof, Zetty Norhana Balia
    • Journal of Plant Biotechnology
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    • v.44 no.4
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    • pp.462-471
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    • 2017
  • Thiamine pyrophosphate (TPP), the active form of thiamine is a cofactor for enzymes involved in central metabolism pathways. However, it is also known to have a role as a stress signaling molecule in response to environmental changes. Anabaena sp. and N. oculata are microorganisms which are abundantly found in Malaysia's freshwater and marine ecosystem. However, not much studies have been done especially in regards to thiamine biosynthesis. This work aimed to amplify of gene transcripts coding for thiamine biosynthesis enzymes besides looking at the expression of thiamine biosynthesis genes upon stress application. Various stress inducers were applied to the cultures and RNA was extracted at different time points. The first two genes, ThiC and ThiG/Thi4 encoding enzymes of the pyrimidine and thiazole branch respectively in the thiamine biosynthesis pathway were identified and amplified. The expression of the genes were analysed via RT-PCR and the intensity of bands were analysed using ImageJ software. The results showed up to 4-fold increase in the expression of ThiC and ThiG gene transcript as compared to control sample in Anabaena sp. ThiC gene in N. oculata showed an expression of 6-fold higher as compared to control sample. In conclusion, stresses induced the expression of the gene coding for one of the most important enzymes in thiamine biosynthesis pathway. This is an agreement with the hypothesis that overexpression of thiamine is crucial in assisting plants to combat abiotic stresses.

A Study on the development of Algorithm for Removing Noise from Road Crack Image (도로면 크랙영상의 노이즈 제거 알고리즘에 관한 연구)

  • Kim Jung-Ryeol;Lee Se-Jun;Choi Hyun-Ha;Kim Young-Suk;Lee Jun-Bok;Cho Moon-Young
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • autumn
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    • pp.535-538
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    • 2002
  • Machine vision algorithms, which are composed of noise elimination algorithm, crack detection and mapping algorithm, and path planning algorithm, are required for sealing crack networks effectively and automation of crack sealing.. Noise elimination algorithm is the first step so that computer take cognizance of cracks effectively. Noises should be removed because common road includes a lot of noises(mark of oil, tire, traffic lane, and sealed crack) that make it difficult the computer to acknowledge cracks accurately. The objective of this paper is to propose noise elimination algorithm, prove the efficiency of the algorithm through coding. The result of the coding is represented in this paper as well.

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A New Predictive EC Algorithm for Reduction of Memory Size and Bandwidth Requirements in Wavelet Transform (웨이블릿 변환의 메모리 크기와 대역폭 감소를 위한 Prediction 기반의 Embedded Compression 알고리즘)

  • Choi, Woo-Soo;Son, Chang-Hoon;Kim, Ji-Won;Na, Seong-Yu;Kim, Young-Min
    • Journal of Korea Multimedia Society
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    • v.14 no.7
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    • pp.917-923
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    • 2011
  • In this paper, a new prediction based embedded compression (EC) codec algorithm for the JPEG2000 encoder system is proposed to reduce excessive memory requirements. The EC technique can reduce the 50 % memory requirement for intermediate low-frequency coefficients during multiple discrete wavelet transform (DWT) stages compared with direct implementation of the DWT engine of this paper. The LOCO-I predictor and MAP are widely used in many lossless picture compression codec. The proposed EC algorithm use these predictor which are very simple but surprisingly effective. The predictive EC scheme adopts a forward adaptive quantization and fixed length coding to encoding the prediction error. Simulation results show that our LOCO-I and MAP based EC codecs present only PSNR degradation of 0.48 and 0.26 dB in average, respectively. The proposed algorithm improves the average PSNR by 1.39 dB compared to the previous work in [9].

An Effective MC-BCS-SPL Algorithm and Its Performance Comparison with Respect to Prediction Structuring Method (효과적인 MC-BCS-SPL 알고리즘과 예측 구조 방식에 따른 성능 비교)

  • Ryug, Joong-seon;Kim, Jin-soo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.7
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    • pp.1355-1363
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    • 2017
  • Recently, distributed compressed video sensing (DCVS) has been actively studied in order to achieve a low complexity video encoder by integrating both compressed sensing and distributed video coding characteristics. Conventionally, a motion compensated block compressed sensing with smoothed projected Landweber (MC-BCS-SPL) has been considered as an effective scheme of DCVS with all compressed sensing frames pursuing the simplest sampling. In this scheme, video frames are separately classified into key frames and WZ frames. However, when reconstructing WZ frame with conventional MC-BCS-SPL scheme at the decoder side, the visual qualities are poor for temporally active video sequences. In this paper, to overcome the drawbacks of the conventional scheme, an enhanced MC-BCS-SPL algorithm is proposed, which corrects the initial image with reference to the key frame using a high correlation between adjacent key frames. The proposed scheme is analyzed with respect to GOP (Group of Pictures) structuring method. Experimental results show that the proposed method performs better than conventional MC-BCS-SPL in rate-distortion.

Vertex selection method considering texture degradation for contour approximation (밝기 왜곡을 고려한 윤곽선 근사화용 정점 선택 방법)

  • Choi Jae Gark;Lee Si-Woong;Koh Chang-Rim;Lee Jong-Keuk
    • Journal of Broadcast Engineering
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    • v.10 no.4 s.29
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    • pp.632-642
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    • 2005
  • This paper presents a new vertex selection scheme for the polygon-based contour approximation. In the proposed method, the entire contour is partitioned into partial segments and they are approximated adaptively with variable accuracy. The approximation accuracy of each segment is controlled based on its relative significance. By computing the relative significance with the texture degradation in the approximation error region, the visual quality enhancement in the reconstructed frames can be achieved under the same amount of the contour data. For this purpose, a decision rule for $d_{max}$ is derived based on inter-region contrasts. In addition, an adaptive vertex selection method using the derived rule is proposed. Experimental results are presented to show the superiority of the proposed method over conventional methods.

A Video Watermarking Method using Global Masking (전역 마스킹을 이용한 비디오 워터마킹 방법)

  • 문지영;호요성
    • Journal of Broadcast Engineering
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    • v.8 no.3
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    • pp.268-277
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    • 2003
  • In this paper, we propose a new video watermarking method exploiting the human visual system (HVS) to find effective locations. in the video frames which make the watermark robust and imperceptible simultaneously. In particular, we propose a new HVS-optimized weighting map for hiding the watermark by considering HVS in three different aspects : frequency, spatial, and motion masking effects. The global masking map is modeled by combining the frequency masking, the spatial masking, and the motion masking. In this paper, we use a watermark which is generated by the bitwise exclusive-OR operation between a logo image and a random sequence. The amount of watermarks is weighted by a control parameter. Furthermore, we embed the watermark in the uncompressed video sequence for the general watermarking method available to various coding schemes. Simulation results show that the watermark is imperceptible and the proposed method is good for watermark capacity. It is also demonstrated that the proposed method is robust against various attacks, such as MPEG coding, MPEG re-encoding, and frame attacks.

FPGA Design of Motion JPEG2000 Encoder for Digital Cinema (디지털 시네마용 Motion JPEG2000 인코더의 FPGA 설계)

  • Seo, Young-Ho;Choi, Hyun-Jun;Kim, Dong-Wook
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.3C
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    • pp.297-305
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    • 2007
  • In the paper, a Motion JPEG2000 coder which has been set as the standard for image compression by the Digital Cinema Initiatives (DCI), an organization composed of major movie studios was implemented into a target FPGA. The DWT (Discrete Wavelet Transform) based on lifting and the Tier 1 of EBCOT (Embedded Block Coding with Optimized Truncation) which are major functional modules of the JPEG2000 were setup with dedicated hardware. The Tier 2 process was implemented in software. For digital cinema the tile-size was set to support $1024\times1024$ pixels. To ensure the real-time operations, three entropy encoders were used. When Verilog-HDL was used for hardware, resources of 32,470 LEs in Altera's Stratix EP1S80 were used, and the hardware worked stably at the frequency of 150Mhz.

A Spatially Adaptive Post-processing Filter to Remove Blocking Artifacts of H.264 Video Coding Standard (H.264 동영상 표준 부호화 방식의 블록화 현상 제거를 위한 적응적 후처리 기법)

  • Choi, Kwon-Yul;Hong, Min-Cheol
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.8C
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    • pp.583-590
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    • 2008
  • In this paper, we present a spatially adaptive post-processing algorithm for H.264 video coding standard to remove blocking artifacts. The loop filter of H.264 increases computational complexity of the encoder. Furthermore it doesn't clearly remove the blocking artifacts, resulting in over-blurring. For overcoming them, we combine the projection method with the Constraint Least Squares(CLS) method to restore the high quality image. To reflect the Human Visual System, we adopt the weight norm CLS method. Particularly pixel location-based local variance and laplacian operator are newly defined for the CLS method. In addition, the fact that correlation among adjoining pixels is high is utilized to constrain the solution space when the projection method is applied. Quantization Index(QP) of H.264 is also used to control the degree of smoothness. The simulation results show that the proposed post-processing filter works better than the loop filter of H.264 and converges more quickly than the CLS method.

Automatic Generation of the Personal 3D Face Model (3차원 개인 얼굴 모델 자동 생성)

  • Ham, Sang-Jin;Kim, Hyoung-Gon
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.36S no.1
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    • pp.104-114
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    • 1999
  • This paper proposes an efficient method for the automatic generation of personalized 3D face model from color image sequence. To detect a robust facial region in a complex background, moving color detection technique based on he facial color distribution has been suggested. Color distribution and edge position information in the detected face region are used to extract the exact 31 facial feature points of the facial description parameter(FDP) proposed by MPEG-4 SNHC(Synthetic-Natural Hybrid Coding) adhoc group. Extracted feature points are then applied to the corresponding vertex points of the 3D generic face model composed of 1038 triangular mesh points. The personalized 3D face model can be generated automatically in less then 2 seconds on Pentium PC.

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Fast Computation of DWT and JPEG2000 using GPU (GPU를 이용한 DWT 및 JPEG2000의 고속 연산)

  • Lee, Man-Hee;Park, In-Kyu;Won, Seok-Jin;Cho, Sung-Dae
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.44 no.6
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    • pp.9-15
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    • 2007
  • In this paper, we propose an efficient method for Processing DWT (Discrete Wavelet Transform) on GPU (Graphics Processing Unit). Since the DWT and EBCOT (embedded block coding with optimized truncation) are the most complicated submodules in JPEG2000, we design a high-performance processing framework for performing DWT using the fragment shader of GPU based on the render-to-texture (RTT) architecture. Experimental results show that the performance increases significantly, in which DWT running on modern GPU is more than 10 times faster than on modern CPU. Furthermore, by replacing the DWT part of Jasper which is the JPEG2000 reference software, the overall processing is 2$\sim$16 times faster than the original JasPer. The GPU-driven render-to-texture architecture proposed in this paper can be used in the general image and computer vision processing for high-speed processing.